The present invention relates to the method for processing silver halide color photographic materials and particularly to the method for processing silver halide color photographic materials capable of improving remarkably the processing variation in the color development and of realizing the low environmental pollution.
Generally, color photographic materials produce thereon photographic images after they pass through the processing steps including a color developing step wherein color photographic materials, after they are exposed to light, are processed in the developer containing paraphenylene type color developing agent, a bleaching step and a fixing step or a bleach-fix step in place of previous two steps and a washing step.
In aforesaid color developing step, color images are formed by the coupling reaction between an oxidation product of color developing agent and a color coupler and metallic silver are concurrently produced in the photographic step. The metallic silver are oxidized by bleaching agents in the succeeding desilverizing step and then form, through the aid of fixing agents, the soluble silver complexes which are dissolved away.
Researches for low environmental pollution have been made recently from the viewpoints of an environmental protection and a cost and have been put to practical use in a partial processing steps. Especially in the color developing step, various technologies for low environmental pollution have been proposed in the past due to the level of an influence of the color developing step upon environmental pollution. For example, regenerating methods through an electrolysis described in Japanese Patent Publication Open to Public Inspection Nos. 37731/1979, 1048/1981, 1049/1981, 27142/1981, 33644/1981 and 149036/1981 (hereinafter referred to as Japanese Patent O.P.I. Publication), generating methods by means of activated carbon described in Japanese Patent Examined Publication No. 1571/1980 and Japanese Patent O.P.I. Publication No. 14831/1983, an ion exchange membrane method described in Japanese Patent O.P.I. Publication No. 105820/1977 and methods by means of an ion exchange resin described in Japanese Patent O.P.I Publication Nos. 132343/1978, 144240/1980, 146249/1982 and U.S. Pat. No. 4,348,475 and disclosed. However, aforesaid methods require a large and expensive regenerating apparatus and a skilled person who can analyze regenerating liquid for keeping the development level constant and therefore the methods are not utilized except an occasion where the methods are used by only a few photofinishing laboratories. Recently, on the other hand, a method for reducing waste liquid not by using a regenerating method but by reducing replenisher for the color developer has become popular. This method does not require a large and expensive apparatus and a skilled analyzer and therefore it is a desirable method for achieving low environmental pollution, which is different from aforesaid methods. Through this method, it is possible to attain a low replenishment to a certain extent but this method has serious disadvantages such as the condensation of color developer caused by evaporation, mixing of iron salt and thiosulfate caused by the belt contamination and back contamination and a large process variation and a large process stain both caused by the substances eluted from the emulsion such as, for example, an outflow of activator and inhibitor. This tendency is remarkable especially when the low replenishment is accelerated under the conditions of high temperature processing and low volume processing. As a technology for preventing the process variation caused by iron salt and thiosulfate both mixed into color developer during the low replenishment, various types of chelating agents are disclosed and further polyvinyl pirrolidone type compounds and polyethylene glycol type compounds are disclosed in Japanese Patent O.P.I. Publication Nos. 150847/1982, 120250/1983 and 121036/1983, but all of them only prevent iron salt and thiosulfate both in a small amount to be mixed and they are not so effective when the low replenishment is accelerated and the amount level of iron salt and thiosulfate mixed into color developer is high. Further, when aforesaid chelating agents and polyvinyl pirrolidone type and polyethylene glycol type high molecular compounds are added in abundance, the photographic characteristics of photosensitive materials are adversely affected, which is not desirable.